Human-level intelligence for decision making is not unique. Rather, it evolved from the simplest environmental constraints (e.g., a crossing of cerebral hemispheres in fish to avoid swimming into objects) in the form of situation→action pairs to more-complex constraints in apes (e.g., yellow color in tree likely to be bananas) to the most-complex constraints in humans—still having fundamental origins with transfer learning by analogy to modern tasks. Fast-forwarding to modern intelligent systems presents the need, among many others, to solve a fundamental outstanding problem in case-based-reasoning (CBR); namely, indexing and adaptively generalizing case-based solutions.